Month 12; Hydraulics Section 2 (Book Formulas)

Question 0

Friction Loss Formula

Book Hydraulics

Answer 0

FL = C x Q^2 x L

FL = Friction Loss
C = Coefficient (Constant Factor)
Q = Flow Rate in Gallons Per Minute/100
L = Hose length in feet/100

Question 1

GPM Formula (Solid Stream Tips)

Book Hydraulics

Answer 1

GPM = 29.7 x D^2 x Square Root of NP

29.7 = Constant
D = Diameter of the tip measured in inche
NP - Nozzle Pressure in PSI

Question 2

Coefficients for Common Hose Sizes

1 3/4”
2 1/2”
5”

Answer 2

1 3/4” = 15.5
2 1/2” = 2.0
5” = .08

Question 3

Elevation Loss (EL)

For every foot of elevation change what PSI is gained or lost?

Answer 3

.434psi

Question 4

Engine Pressure

Book Hydraulics

Answer 4

EP = NP + FL + AL +/- EL

EP = Engine Pressure
NP = Nozzle Pressure
FL = Friction Loss
AL = Appliances
EL = Elevation Changes

Question 5

Combination Nozzle

Nozzle Reaction Formula

Answer 5

NR = .0505 x Q x Square Root of NP

.0505 = A Constant
Q = Quantity GPM
D = Nozzle Tip Diameter
NP = Nozzle Pressure

Question 6

Solid Stream Nozzle

Nozzle Reaction

Answer 6

NR = 1.57 x D^2 x NP

.0505 = Constant
Q = Quantity GPM
D = Nozzle Tip Diameter
NP = Nozzle Pressure

Question 7

Area of a Circle Equation

Answer 7

Pie R^2

or

D^2 x .7854

Question 8

Volume of a Cylinder

Answer 8

Pie R^2 x L

Or

D^2 x .7854 X L

Question 9

Velocity of Water from a port or solid stream nozzle

Answer 9

V = 12.14 x Square Root of Nozzle Pressure

V = Velocity
12.14 = Constant
NP = Nozzle Pressure

Question 10

Engine Pressure Formula

Answer 10

EP = NP + FL +/- H

EP = Engine Pressure
NP = Nozzle Pressure
H = Height or Head (elevation) = .434 per foot

Question 11

Engine Pressure Formula with No GPMs

Only for Solid Bore Tips

Answer 11

EP = NP x (1.1 + K x L)

NP = Nozzle Pressure
K = Co-efficient for friction loss based upon nozzle diameter
L = Length of Hose per 100ft.

Question 12

If you know your engine pressure but want to learn the nozzle pressure.

Only solid bore nozzles.

Answer 12

NP = EP/ (1.1 + K * 1.5)

Question 13

Nozzle Reaction for Combination Nozzles

Answer 13

NR = .0505 x Q x Square Root of NP

NR = Nozzle Reaction
Q = Gallons per minute
NP = Nozzle Pressure

Question 14

Nozzle Reaction Solid Bore Nozzles

Answer 14

NR = 1.57 x D2 X NP

NR = Nozzle Reaction
D = Diameter of nozzle in inches
NP = Nozzle Pressure

Question 15

Velocity Formulas

Answer 15

V = 12.14 Square Root NP

OR

V = 8 Square Root H

V = Velocity in feet/second
NP = Nozzle Pressure
H = Head or Elevation

Question 16

Reach Formula

Answer 16

S = 1/2NP + 26 + X

S = Horizontal distance in feet
NP = Nozzle Pressure
X = if tips is > 3/4" then add 5 for each 1/8" increase in tip size greater than 3/4"